Systems for three-dimensional optical scanning are well known in the prior art. They typically comprise one or more light sources projecting a structured light pattern on the object to be scanned, one or more cameras and data processing equipment to convert the recorded image co-ordinates to three dimensional co-ordinates using state of the art software. Usually, only a part of the object is scanned in a single scan. To create a full scan of the object, camera and light source need to be moved relative to each other.
Precision is of utmost importance in many applications, e.g. when the scan data is used to model an object, which must fit precisely into another part. Such applications are e.g. devices for the ear canal such as hearing aids, dental implants and other prostheses for the body. For hearing aid shells sub-millimeter precision is required or the shell will cause irritation, acoustic feedback and possibly infection to the epidermis of the ear canal. For dental implants the precision requirement is even greater, since a human being can detect differences less than 1/10 of a millimeter when biting. Therefore systematic or random errors in the calibration and/or performance of scanners for these uses can be critical. This has hitherto limited the use of scanning in the modeling of such implants and shells.
When scanning an object in a three-dimensional scanner, the object can be placed on a plate, platform, holding device, clamping device etc. in the scanner.
The article “Erzeugung von CAD-Datensätzen für Inlays and Kronen” by Mehl et al. in “Deutsche Zahnärtzliche Zeitschrift, 52. Jahrgang” discloses a clamping device for securing teeth preparations to be scanned in a 3D scanner. The preparations is taken from a sectioned gypsum model of a teeth set of a patient.
It remains a problem to provide an object feeder where the objects can be scanned easily, effectively and reliably.